/*

This file is part of roomyak.

Copyright (C) 2008 Pixecur Technologies Incorporated (Esotera).
Visit Esotera at http://www.esoteras3.com
 
roomyak is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
 
roomyak is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with roomyak; see the file COPYING.  If not, write to 
Pixecur Technologies, 213-31 Peet Street, St. John's, NL, A1B 3W8. 
 
Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.
 
*/

package com.datasentinel.util.concurrent;

import java.util.HashMap;
import java.util.Map;


/*
 * TODO: Make this reentrable and thread ID dependant.
 */
public class ReadWriteLockContainer<E extends Comparable<E>>
{
	private Map<E, LockMode> lockMap;
	
	public ReadWriteLockContainer()
	{
		lockMap = new HashMap<E, LockMode>();
	}

	public synchronized boolean tryReadLock(E object)
	{
		LockMode lockMode = lockMap.get(object);
		
		if(lockMode == null)
		{
			lockMap.put(object, LockMode.READ);
			return true;
		}
		else if(lockMode == LockMode.READ)
		{
			return true;
		}
		
		return false;
	}
	public synchronized boolean tryWriteLock(E object)
	{
		LockMode lockMode = lockMap.get(object);
		
		if(lockMode == null)
		{
			lockMap.put(object, LockMode.WRITE);
			return true;
		}

		return false;
	}	

	public synchronized void unlock(E object)
	{
		lockMap.remove(object);
	}

}
